Note 10 - Income Taxes (Tables)

12 Months Ended

Dec. 31, 2016

Notes Tables

Schedule of Deferred Tax Assets and Liabilities [Table Text Block]

	December 31,
	201 6			201 5
Deferred tax assets:
Net operating loss carryforwards	$	3,550		$	3,395
Research credit carryforwards		235			236
Accrued expenses		188			—
Stock-based compensation		420			148
Other		79			32
Total deferred tax assets		4,472			3,811
Valuation allowance		(4,472	)		(3,811	)
Net deferred tax asset	$	—		$	—

Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]

	Year Ended December 31,
	2016			2015
Statutory rate		34.0	%		34.0	%
Permanent differences		(4.0	)		(10.3	)
State tax rate true-up		0.6			5.3
Valuation allowance		(30.7	)		(29.0	)
Other		(0.1	)		(0.1	)
State and local income taxes		—			0.1
Effective rate		0.0	%		0.0	%

Summary of Operating Loss and Tax Credit Carryforwards [Table Text Block]

	Amount (In thousands)		Expiration Years
Net operating losses—federal	$	10,441	Beginning 2031
Tax credits—federal		235	Beginning 2041